Twenty patients with various stages of RA were examined. They included: 1) 7 cases in Steinbroker stage 1 (onset); 2) 13 cases in Steinbroker stage 2-3 (chronic). The group was divided into 16 treated and 4 untreated cases. Monoclonal antibodies were used to assay T3, T4, T8 and T4/T8 ratio and the results were compared with those in a control group. The results showed a T8 deficit and a consequent change in the T4/T8 ratio in untreated subjects with "onset" RA. The immune situation of the chronic and treated cases was very similar to that in the control group probably as a result of treatment.